Existing environmental control systems can be used to control individual environmental control devices, such as lights, doors, audio equipment, HVAC equipment, and the like, though the convenience of controlling one device at a time through an environmental control system is not much different than controlling each device via its conventional controller (such as a light switch, a thermostat, a garage door opener, a stereo, etc.).
Existing environmental control systems can be programmed to implement “scenes” by sending commands to multiple environmental control devices. A scene may be programmed for a particular time of day, so that activating a remote control in the morning may trigger a set of lights, setting the HVAC to a certain level, turning on a stereo to a radio station, and starting a coffee maker, whereas activating the remote control in the evening may trigger a different scene which may open the garage door, turn on a different set of lights, set the HVAC to a different level, and the like.
However, scenes can be difficult to program and having two scenes instead of one adds to the system complexity. Exceptions to the program can be programmed, though this results in greater programming complexity as well as remote controls with multiple activation options to account for the exceptions—further adding to the overall system complexity. As a result, changing scene programs can be complex, often requiring service by technicians with special skills to accomplish what should be routine changes.